The use of continuous time filters that utilize one or more transconductor stages and having a bandwidth that is a function of the tranconductance G.sub.m of each of the stages is becoming more widespread. This G.sub.m value can vary as a result of process variations, temperature variations, etc. Consequently, the bandwidth can also vary as a result of these variations in process and temperature, up to 100% from the desired frequency. For some applications, the bandwidth itself must be programmable. This is typically achieved by varying the G.sub.m via some programmable device such as a digital-to-analog converter (DAC) which receives a digital program word and converts it to an analog program signal. This programming device typically has a nonlinear transfer function such that any compensation mechanism that compensates for process and temperature variations of the G.sub.m of a particular transconductor in the filter will be required to operate over the bandwidth of the device.
One prior art compensated transconductor element for use with a continuous time filter has associated therewith a transconductance portion for converting a differential input voltage to a differential current output. During a calibration cycle, an external programmable current source is utilized for inserting a predetermined amount of current into the output of the filter while a fixed voltage is provided to the input of the filter. The programmable input current is fixed such that when the transconductance of the transconductance is set, the effective current output will be at a "0" value. By comparing the actual output current value with the desired output value of "0", an error signal can be generated, which error signal is then utilized in a negative feedback loop to tune the transconductance of the transconductance element. Since the fixed input voltage and the programmable current source are fixed values, this provides a current/voltage relationship by which to determine the transconductance of the overall transconductor.